A book, physically, is typically a set or collection of written, printed, illustrated, or blank sheets, made of ink, paper, parchment, or other materials, usually fastened together to hinge at one side. In 2010, Google estimated that since the invention of printing, approximately 130,000,000 unique titles had been published.
Modern paper books are generally printed on papers which are designed specifically for the publication of printed books. Typically, books papers are light weight papers specified by their caliper/substance ratios (volume basis). Different paper qualities are used as book paper depending on type of book. As such, common paper grades used include Machine finished coated papers, wood free uncoated papers, coated fine papers and special fine papers.
Whether books are hardback or paper back, and whether they are large or small, thick or thin or of various materials and dimensions, there is a pressing need to protect books so as not to bend the books, expose the pages to ware and tear etc. This is particularly necessary in the case of soft cover books, where a paperback or paper based cover is used.
It would be highly advantageous to have a simple and easy mechanism for protecting book covers and books from bending, fraying, ripping, and otherwise getting damaged.